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A low cost CAN bus load transducer, requiring only a few low cost components, has been developed. Traditionally, to ascertain CAN bus loading, an algorithm based upon a number of assumptions executed on a microcontroller is required. This has many disadvantages that include being potentially costly, inaccurate and can take up a significant amount of processing, especially under higher bus load situations causing a higher number of interrupts. However, the CAN bus load transducer developed, is connected to the CAN bus and outputs a varying signal proportional to bus loading. A microcontroller can then simply be used to read the bus load signal and covert it into percentage bus loading as often as is required. The method is inexpensive, accurate and provides a continuous signal for CAN bus loading measurement that does not become expensive in terms of processing under higher bus load conditions. In this paper, the application of the CAN bus load transducer technology is explored.

The Controller Area Network (CAN) has seen enormous success in automotive body and powertrain control systems. However, there is a change in emphasis arising in the industry in which CAN is seen as too powerful and expensive for simple digital body control applications, but not robust or fast enough for more safety critical applications such as the envisaged Drive-by-Wire systems of future passenger cars. The emerging protocols Local Interconnect Network (LIN), the Time Triggered Protocols (TTP/A, TTP/C), Time Triggered CAN (TTC) and Byteflight are examined in terms of their application and likelihood for future success. The paper is concluded with comments concerning a newly announced protocol known as FlexRay.

The popularity of CAN (Controller Area Network) in the production vehicles is well established. As a result, CAN has been developed for use in many non-automotive applications. This gave rise to the development of an open higher layer CAN protocol known as DeviceNet. With the popularity of DeviceNet for Automation Systems, this technology has drastically decreased in cost. Although DeviceNet is quite complex to develop, it easier to implement than SAE J1939 due to the large number of commercial off-the-shelf product that is available. Also, there are many configuration and diagnostic tools available by the same means. There are more than 300 vendors of DeviceNet product. Researchers at the University of Warwick have built a vehicle demonstrator using CAN/DeviceNet modules. This paper will illustrate the ease of vehicle system integration utilising this popular technology.